Clock signals are generally used in integrated circuits (ICs), and may be used, for example, for the purpose of timing control, synchronization, and the like. Clock signals can be provided by a clock system, which may include various clock circuits, such as clock generation circuit, clock driving circuit, and the like. Conventionally, a device on an IC, such as a flip-flop, is responsive to one type of edges, either rising edges or falling edges, of a clock signal.